.siblings {
  display: flex;
  flex-wrap: wrap;
}

.sibling {
  position: relative;
  width: 8px;
  height: 8px;
  margin: 0 2px 2px 0;
  padding: 0px;

  outline: 1px solid mistyrose;
  background-color: transparent;
}

mat-progress-spinner {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
}

.sibling div {
  position: absolute;
  width: 100%;
  height: 100%;
}
.sibling div.filled {
  background-color: orange;
}
